Functional morphology and paleoecology of Pilosa (Xenarthra, Mammalia) based on a two-dimensional geometric Morphometrics study of the Humerus.

The relationship between humerus shape and the modes of exploring substrate among extinct and extant Pilosa (especially anteaters and ground sloths) were investigated here. We used geometric morphometrics and discriminant analyses to relate morphological patterns and their possible ecological categories. Our results suggest that plesiomorphic taxa such as Nothrotheriidae, most Megalonychidae and basal Megatheriidae tend to have more slender humerus, associated to generalist habitus (climbing, swimming and digging activities), and while Mylodontidae developed specialized digging habitus. Additionally, we inferred ground sloths which inhabited the Brazilian territory during the Quaternary likely occupied at least four different niches. Mammals display morphofunctional adaptations on the limbs which are reflected on their modes of substrate exploration. Herein, we analyzed the humerus morphology of ground sloths and anteaters. Our results suggest that most of the Pleistocene Mylodonts were fossorial taxa, while most of the Santacrucian sloths plus extant anteaters were semiarboreal or semiaquatic taxa. The Pleistocene Megatheriidae should be ambulatory.

Inhibition of PDE5 Restores Depressed Baroreflex Sensitivity in Renovascular Hypertensive Rats.

Renal artery stenosis is frequently associated with resistant hypertension, which is defined as failure to normalize blood pressure (BP) even when combined drugs are used. Inhibition of PDE5 by sildenafil has been shown to increase endothelial function and decrease blood pressure in experimental models. However, no available study evaluated the baroreflex sensitivity nor autonomic balance in renovascular hypertensive rats treated with sildenafil. In a translational medicine perspective, our hypothesis is that sildenafil could improve autonomic imbalance and baroreflex sensitivity, contributing to lower blood pressure. Renovascular hypertensive 2-kidney-1-clip (2K1C) and sham rats were treated with sildenafil (45 mg/Kg/day) during 7 days. At the end of treatment, BP and heart rate (HR) were recorded in conscious rats after a 24-h-recovery period. Spontaneous and drug-induced baroreflex sensitivity and autonomic tone were evaluated; in addition, lipid peroxidation was measured in plasma samples. Treatment was efficient in increasing both spontaneous and induced baroreflex sensitivity in treated hypertensive animals. Inhibition of PDE5 was also capable of ameliorating autonomic imbalance in 2K1C rats and decreasing systemic oxidative stress. Taken together, these beneficial effects resulted in significant reductions in BP without affecting HR. We suggest that sildenafil could be considered as a promising alternative to treat resistant hypertension.

Accuracy of plasma interleukin-18 and adiponectin concentrations in predicting metabolic syndrome and cardiometabolic disease risk in middle-age Brazilian men.

The aims of this cross-sectional study were to explore the ability of serum interleukin 18 (IL-18) and adiponectin to identify metabolic syndrome (MetS), and to verify their association with an index of central lipid overaccumulation (lipid accumulation product (LAP)) and cardiometabolic risk factors in a population of middle-aged Brazilian men. A group of 218 apparently healthy middle-aged Brazilian men (age, 50.3 ± 4.97 years) underwent anthropometric, clinical, sociodemographic, and standard serum biochemical assessments. LAP was calculated and the study participants were categorized into 3 groups according to serum IL-18 and adiponectin cut-points tertiles to verify the association of these biomarkers with cardiometabolic risk factors. The MetS group had more less active (p = 0.03) and obese (p < 0.01) individuals who exhibited higher IL-18 (p < 0.01) and lower adiponectin (p < 0.01) than did those in the group with no MetS. After adjustments (age, smoking, alcohol consumption, physical activity level, and total body fat), serum IL-18 ≥ 336.4 pg/mL was an independent factor for MetS occurrence and it was directly associated with LAP (≥51.28), central obesity, hypertriglyceridemia, and hypertension (p < 0.05), but not with high-density lipoprotein cholesterol (HDL-C). Serum adiponectin ≥ 7.02 µg/mL was negatively associated with MetS occurrence, LAP, hypertriglyceridemia, and low HDL-C (p < 0.05), but not with central obesity and hypertension. In conclusion, both IL-18 and adiponectin demonstrated the ability to identify MetS in this population, with IL-18 being more accurate. The association of these biomamarkers with LAP and cardiometabolic risk factors highlights its relevance as a diagnostic tool.

Attenuation of Ca2+ homeostasis, oxidative stress, and mitochondrial dysfunctions in diabetic rat heart: insulin therapy or aerobic exercise?

We tested the effects of swimming training and insulin therapy, either alone or in combination, on the intracellular calcium ([Ca(2+)]i) homeostasis, oxidative stress, and mitochondrial functions in diabetic rat hearts. Male Wistar rats were separated into control, diabetic, or diabetic plus insulin groups. Type 1 diabetes mellitus was induced by streptozotocin (STZ). Insulin-treated groups received 1 to 4 UI of insulin daily for 8 wk. Each group was divided into sedentary or exercised rats. Trained groups were submitted to swimming (90 min/day, 5 days/wk, 8 wk). [Ca(2+)]i transient in left ventricular myocytes (LVM), oxidative stress in LV tissue, and mitochondrial functions in the heart were assessed. Diabetes reduced the amplitude and prolonged the times to peak and to half decay of the [Ca(2+)]i transient in LVM, increased NADPH oxidase-4 (Nox-4) expression, decreased superoxide dismutase (SOD), and increased carbonyl protein contents in LV tissue. In isolated mitochondria, diabetes increased Ca(2+) uptake, susceptibility to permeability transition pore (MPTP) opening, uncoupling protein-2 (UCP-2) expression, and oxygen consumption but reduced H2O2 release. Swimming training corrected the time course of the [Ca(2+)]i transient, UCP-2 expression, and mitochondrial Ca(2+) uptake. Insulin replacement further normalized [Ca(2+)]i transient amplitude, Nox-4 expression, and carbonyl content. Alongside these benefits, the combination of both therapies restored the LV tissue SOD and mitochondrial O2 consumption, H2O2 release, and MPTP opening. In conclusion, the combination of swimming training with insulin replacement was more effective in attenuating intracellular Ca(2+) disruptions, oxidative stress, and mitochondrial dysfunctions in STZ-induced diabetic rat hearts.

Red but not white meat consumption is associated with metabolic syndrome, insulin resistance and lipid peroxidation in Brazilian middle-aged men.

BACKGROUND: The influence of diet on metabolic syndrome and oxidative stress are not completely known. DESIGN: This cross-sectional study assessed the association of red meat and white meat consumption with metabolic syndrome, insulin resistance and lipid peroxidation in Brazilian middle-aged men. METHODS: A total of 296 subjects (age: 50.5 ± 5.0 years, body mass index: 25.8 ± 3.5 kg/m(2)) were evaluated. Anthropometry, lifestyle features, blood biochemical parameters, diagnosis of metabolic syndrome, homeostatic model assessment for insulin resistance, a lipid peroxidation marker (oxidized low-density lipoprotein) and triglycerides:high-density lipoprotein cholesterol ratio were assessed. Dietary intake was estimated by a food frequency questionnaire. RESULTS: The subjects included in the highest tertile red meat (≥81.5 g/d) and saturated fatty acid from red meat consumption (≥4.3 g/d) had higher occurrence of central obesity (nearly 60%, p < 0.01), hypertriglyceridaemia (nearly 43%, p < 0.01) and metabolic syndrome (35%, p < 0.01). They also had higher values of homeostatic model assessment for insulin resistance, oxidized low-density lipoprotein, and triglycerides:high-density lipoprotein cholesterol ratio, regardless of interfering factors. There were no associations of highest white meat tertile (≥39.4 g/d) and saturated fatty acid from white meat (≥1.0 g/d) consumption with the assessed parameters (p > 0.05). CONCLUSIONS: Red meat consumption was cross-sectionally associated with the occurrence of central obesity, hypertriglyceridaemia, and metabolic syndrome as well as with higher homeostatic model assessment for insulin resistance, oxidized low-density lipoprotein concentrations and triglycerides:high-density lipoprotein cholesterol ratio. The content of saturated fatty acid from red meat consumption may be a factor that contributed to this relationship, while white meat consumption was not associated with metabolic syndrome and the assessed biomarkers.

The impact of serum uric acid on the diagnostic of metabolic syndrome in apparently healthy brazilian middle-aged men.

BACKGROUND: Hyperuricemia is related to Metabolic Syndrome (MetS) and cardiovascular diseases, but the use of serum uric acid (UA) to diagnose MetS is currently ignored in clinical practices. OBJECTIVES: To examine the impact of serum UA on the diagnostic of MetS and the relationship of serum UA with cardiometabolic risk factors in apparently healthy Brazilian middle-aged men residents in a city of Minas Gerais. METHODS: In a cross-sectional analysis, 289 apparently healthy middle-aged men underwent anthropometric, clinical, sociodemographic and blood serum biochemical evaluation. By using receive operating curve the internal cutoff of serum UA was determined (5.25 mg/dL). RESULTS: Subjects with two or more components of MetS exhibited higher serum UA as compared to those with one or none component. The inclusion of serum UA ≥ 5.25mg/dL as an additional component of MetS increased the occurrence of this syndrome by 13%. Subjects with UA ≥ 5.25mg/dL showed high prevalence for MetS and association with its components (central obesity, hypertriglyceridemia, dyslipidemia and hypertension) as well as atherogenic risk. CONCLUSIONS: Serum UA has an important impact on the diagnostic of MetS and is related to cardiometabolic risk factors in apparently healthy Brazilian middle-aged men. Its use in clinical practices could aggregate accuracy to diagnose MetS.

Introducción: La hiperuricemia viene sido asociada con el sindrome metabolico (SM) y las enfermedades cardiovasculares, pero el uso del acido urico (AU) en el diagnostico del SM es comunmente ignorado en la practica clinica. Objetivos: Investigar el impacto de las concentraciones de AU en el diagnostico del SM y la asociacion del AU serico con los factores de riesgo cardiometabolico en brasilenos de mediana edad aparentemente saludables residentes en una ciudad de Minas Gerais. Métodos: Por medio de un analisis transversal, 289 hombres de mediana edad aparentemente saludables fueron sometidos a evaluaciones para determinaciones de variables antropometricas, clinicas, sociodemograficos y bioquimicas. Para determinar el mejor punto de corte para la concentracion del AU serico con respecto al diagnostico del SM (5.25 mg/dL) fue utilizada la curva ROC. Resultados: Sujetos con dos o mas componentes del SM han demostrado mayores concentraciones sericas de AU cuando comparados con individuos con uno o ninguno componente. Ademas, la inclusion del AU > 5.25 mg/dL como un componente adicional en el diagnostico del SM aumento la ocurrencia de este sindrome en un 13%. Finalmente, los hombres con AU ≥ 5.25mg/dL presentaron una asociacion positiva con componentes del SM (obesidad central, hipertrigliceridemia, dislipemia e hipertension arterial), asi como un mayor riesgo aterogenico. Conclusión: AU serico tiene un relevante impacto en la ocurrencia del SM, asi como es asociado a reconocidos factores de riesgo cardiometabolico en brasilenos de mediana edad aparentemente saludables y, su uso en la practica clinica podria anadir en la exactitud del diagnostico del SM.

Waist circumference measures: cutoff analyses to detect obesity and cardiometabolic risk factors in a Southeast Brazilian middle-aged men population--a cross-sectional study.

BACKGROUND: Low-cost practical and reliable tools to evaluated obesity-related cardiometabolic diseases are of clinical practice and public heath relevance worldwide. The aims of this cross-sectional study were to determine the anatomical point of waist circumference that best identify overweight, obesity and central obesity in Southeast Brazilian middle-aged men and to test the relationships of its cutoff points with metabolic syndrome (MetS), insulin resistance (IR) and cardiometabolic risk factors. METHODS: Three hundred men [age: 51 (47-54)] underwent anthropometric, body composition, clinical, sociodemographic and blood plasma biochemical evaluations. RESULTS: The umbilical line circumference (WCUL) was the best predictor for overweight (total body fat ≥ 20%; cutoff point: 88.8 cm), obesity (total body fat ≥ 25%; cutoff point: 93.4 cm) and central obesity (abdominal area fat ≥ 34.6%; cutoff point: 95.6 cm) as measured by dual beam X-ray absorptiometry. Subjects with WCUL ≥ 88.8 cm or ≥ 93.4 cm showed significantly higher values for MetS, IR and cardiometabolic risk factors (i.e. glucose and lipid profiles, blood pressure). The occurrence of WCUL ≥ 88.8 cm was positively associated (p <0.01) with the prevalence of MetS and cardiometabolic risk factors and increased the central obesity prevalence by 19.3% while that of WCUL ≥ 93.4 cm was associated with the prevalence of MetS, IR and cardiometabolic risk factors. CONCLUSIONS: WCUL measure seems to be the best predictor for overweight, obesity and central obesity in urban residents Southeast Brazilian middle-aged men; and the WCUL cutoff point (88.8 cm) is significantly associated with MetS, IR and cardiometabolic risk factors in the studied population.

Usual dietary glycemic load is associated with cardiometabolic risk factors in physically active Brazilian middle-aged men.

INTRODUCTION: The effects of dietary glycemic load (GL) on cardiometabolic risk factors in physically active subjects are not completely known. OBJECTIVE: This cross-sectional study assessed the association of habitual dietary GL with cardiometabolic risk factors in physically active Brazilian middle-aged men. METHODS: One-hundred seventy-six subjects (Age: 50.6 ± 5.0 years, BMI: 25.5 ± 3.6 kg/m2) were evaluated. Anthropometry, lifestyle features, insulin resistance, oxidative stress biomarkers (8-iso-prostaglandin F2α; 8-iso-PGF2α and 8- hydroxydeoxyguanosine; 8-OHdG) and lipid profile were assessed. Dietary intake was estimated through a quantitative food frequency questionnaire. RESULTS: The dietary GL was positively associated with free fatty acid concentrations (ß= 0.311, r2 = 0.13, P-value = 0.034) and triglycerides/HDL cholesterol ratio (ß = 0.598, r2 = 0.19, P-value = 0.028) regardless of confounding factors (central obesity, red meat consumption, age and energy intake). The oxidative stress biomarker, 8-OHdG, was associated with habitual dietary GL (ß = 0.432, r2 = 0.11, P-value = 0.004), regardless of previous confounding factors plus excessive alcohol consumption, iron intake and current smoking status. CONCLUSIONS: The dietary GL was positively associated with lipid profile (free fatty acid concentrations and triglyce rides/HDL cholesterol ratio) and oxidative stress biomarker (8-OHdG). These results indicate potential harmfulness of diet with higher GL to cardiometabolic risk factors in middle-aged men, even in physically active individuals.

Introducción: Los efectos de la carga glucémica (CG) de la dieta sobre los factores de riesgo cardiometabólico en sujetos físicamente activos no están establecidos por completo. Objetivo: Este estudio transversal evaluó la asociación entre la CG de la dieta habitual y los factores de riesgo cardiometabólico en hombres brasileños de mediana edad físicamente activos. Métodos: Ciento setenta y seis sujetos (índice de masa corporal: 25,5 ± 3,6 kg/m2; edad: 50,6 ± 5,0 años) fueron evaluados. Antropometría, características del estilo de vida, la resistencia a la insulina, biomarcadores del estrés oxidativo (8-iso-prostaglandina F2, 8-iso-PGF2y 8 hidroxideoxiguanosina, 8-OHdG) y el perfil lipídico fueron evaluados. La ingesta dietética se estimó por medio de un cuestionario cuantitativo de frecuencia de consumo. Resultados: La CG de la dieta se asoció positivamente con las concentraciones de ácidos grasos libres (= 0,311, r2 = 0,13, P = 0,034) y la razón triglicéridos/colesterol HDL (= 0,598, r2 = 0,19, P = 0,028), independientemente de los factores de confusión (obesidad central, consumo de carne roja, edad e ingesta calórica). El biomarcador del estrés oxidativo, 8-OHdG, también se asoció con CG de la dieta habitual (= 0,432, r2 = 0,11, P = 0,004), independientemente de los factores de confusión anteriores más el consumo excesivo de alcohol, la ingesta de hierro y tabaquismo actual. Conclusiones: La CG de la dieta se asoció positivamente con el perfil lipídico (concentraciones de ácidos grasos libres y razón triglicéridos/HDL colesterol) y el biomarcador de estrés oxidativo 8-OHdG. Estos resultados indican el potencial de nocividad de una dieta con mayor CG respecto a los factores de riesgo cardiometabólico en hombres de mediana edad, incluso en aquellos físicamente activos.

Benefits and relationship of steps walked per day to cardiometabolic risk factor in Brazilian middle-aged men.

OBJECTIVES: We evaluated the benefits and relationship of the number of steps per day to the cardiometabolic risk factors: adiposity indicators; insulin resistance; and metabolic syndrome (MetS) in apparently healthy Brazilian middle-aged men. DESIGN: Cross-sectional. METHODS: Apparently healthy men (age: 50 ± 5 years; n=299) were studied. The number of steps per day was measured by pedometer. The adiposity indicators (waist circumference, total body fat, android and gynoid body fat), serum insulin, glucose and triglycerides, triglycerides/high-density lipoprotein cholesterol (HDL-c) ratio, homeostasis model assessment of insulin resistance (HOMA-IR) and MetS were assessed. Subjects were placed in groups to reflect different levels of steps per day (average of 7 consecutive days): Group 1<10,000 and Group 2 ≥ 10,000. Relationships among variables were measured by multiple linear regressions and the Spearman correlation coefficient as appropriate (p<0.05). RESULTS: The cardiometabolic risk factors were lower (p<0.05) in Group 2 than in Group 1. The number of steps per day was a negative predictive factor for total body fat, android and gynoid body fat and HOMA-IR independent of age, working position, android fat, overweight/obesity prevalence, and triglycerides/HDL-c ratio. Moreover, there was a negative correlation between the number of steps and total body fat, android and gynoid body fat, HOMA-IR and MetS. CONCLUSIONS: Brazilian middle-aged men performing more than 10,000 steps per day have better cardiometabolic conditions than those walking fewer than 10,000 steps. The number of steps per day is inversely related to the indicators of total and regional adiposity, insulin resistance and MetS.